Antiproliferative activity, antioxidant capacity and chemical composition of extracts from the leaves and stem of Chresta sphaerocephala

In this study, antiproliferative and antioxidant activities of crude extracts (hexane, ethyl acetate and methanol) from leaves and stem of Chresta sphaerocephala DC., Asteraceae, were investigated. Antiproliferative activity was tested in vitro against ten human cancer cells and against VERO (no cancer cell). Antioxidant activities were determined using DPPH and ORAC-FL assays and the total phenolic content was estimated by FolinCiocalteu method. Hexane and ethyl acetate extracts (leaves and stem) exhibited antiproliferative activity against cancer cell lines with total growth inhibition (TGI) between 50.40 and 250 mu g/ml. For VERO cell, TGI values were >250 mu g/ml for all extracts, except to hexane extract of the stem (TGI 80.92 mu g/ml). In an initial evaluation, ethyl acetate and methanol extracts (leaves and stem) have shown levels of phenolic compounds between 6.94 and 30.96 mg GAE/kg in FolinCiocalteu assay, DPPH free-radical scavenging activity with SC50 in the range of 75.22 and 400 mu g/ml and antioxidant capacity between 290.08 and 1088 mu mol TE/g of extract in ORAC-FL assay. HPLC-DAD and ESI-MS analysis allowed the identification of flavonoids in the methanol extract from the leaves of C. sphaerocephala. Three steroids and nine triterpenoids were identified in the bioactive hexane extracts using HRGC. (C) 2015 Sociedade Brasileira de Farmacognosia. Published by Elsevier Editora Ltda. All rights reserved.